-LRB- CNN -RRB- -- A young , beloved teacher found killed in the woods . A 14-year-old student in custody , charged with her murder .

That much we know . But hours after both were found -- one dead , one alive -- in suburbs northeast of Boston , much remains unknown as to why Colleen Ritzer was brutally slain .

`` It 's just surreal how quickly someone can go , and how much we take for granted everyday , '' said Danvers High School student Chris Weimert , describing Ritzer as `` the nicest teacher you could ever have . ... I ca n't believe it . ''

Authorities had been looking for the student , Philip Chism , first , after he was reported missing -- with police sending out messages via Twitter and Facebook on Tuesday evening , noting he 'd been last seen around 6:30 p.m. and asking for the public 's help in finding him .

They got a call around 11:20 p.m. about another missing person , 24-year-old Ritzer , after she , too , had n't returned home and was not answering her phone , according to Essex County District Attorney Jonathan Blodgett .

A flurry of activity came next . Police in Topsfield , the town just north of Danvers , around 12:30 a.m. spotted Chism walking alongside a busy road there .

Authorities also converged on Danvers High -- where Ritzer taught and which Chism attended -- finding blood in a second-floor bathroom , the district attorney said . The teacher 's body was soon discovered behind the school .

Chism was tied to Ritzer 's death after police interviewed him and reviewed video surveillance from the school , a criminal complaint states . In court , it was alleged the teenager `` did assault and beat '' Ritzer , leading to her death .

`` Based on his statements and the corroborating evidence found at multiple scenes at ... Danvers High School and surrounding wooded area , the juvenile was subsequently placed into custody and booked for murder , '' adds the complaint .

Read the complaint

The 14-year-old was arraigned Wednesday afternoon in a Salem , Massachusetts , court for murder , then ordered held without bail . A grand jury could decide if Chism will be charged as an adult .

Meanwhile , the tight-knit community of Danvers is at a loss to explain why someone might take the life of Ritzer , a 24-year-old known for posting inspirational messages on her Twitter account and offering students extra help when they needed it .

As the greater Bay State community paid its respects with a moment of silence before the Boston Red Sox began Game 1 of the World Series at Fenway Park , many heartbroken former students of hers gathered for a vigil outside the town 's high school .

All seven schools in the North Shore town closed Wednesday , as investigators did their work and students and residents mourned the loss of Ritzer . Everything will reopen Thursday except the high school , but counselors and grief specialists will be available there for two hours during the day , said Superintendent Lisa Dana . Classes throughout the town are set to resume Friday , she said .

`` I do n't know why she had to die , '' freshman Spencer Wade said of Ritzer , adding that the mysterious and bloody nature of her death made it even harder to deal with . `` She was such a wonderful person . ''

Suspect had lived in 3 states in recent years

Just Monday , the Danvers Police Department was tweeting its support for families and first responders affected by the shooting death of a Sparks , Nevada , teacher -- allegedly at the hands of a 12-year-old boy .

While no motive has been spelled out in Ritzer 's death , some details have started to emerge about the the young suspect .

Chism attended fourth grade at a Clarksville , Tennessee , elementary school , said Clarksville-Montgomery County , Tennessee , school system spokeswoman Elise Shelton . He then spent fifth grade at Hammock Pointe Elementary in Boca Raton , Florida , according to Palm Beach County school spokesman Owen Torres .

The next three years , he was back in Tennessee at Rossview Middle School in Clarksville , according to Shelton . Then his family moved about 1,150 miles northeast to Massachusetts .

Specifically , he was in Danvers , a town of about 26,000 people , and went to its lone public high school . Students said Chism played soccer there , describing him as somewhat quiet but still an active participant in class who had friends .

`` He ... seemed quiet and reserved , but he just seemed normal , '' said Ariana Edwards , who was in Chism 's English class .

Chism did n't drink , do drugs and came from a good family , one of his closest friends said . He described Chism as a good athlete who was shy at first but eventually warmed up to people , adding he had n't been acting strangely lately .

This friend and others got their first hint something was awry when Chism did n't show up for soccer practice . The team ended up setting out to look for their teammate , after seeing texts that he was missing .

As they and police were looking for him -- and after Ritzer was killed -- Chism went to the movies , a source with knowledge of the investigation said .

Blodgett declined Wednesday to offer specifics on the relationship between the suspect and the late teacher , though his office said Chism attended one of Ritzer 's classes .

When authorities first reported Chism missing on Tuesday , people responded on the police department 's Facebook page with prayers for his `` safe return . '' One neighbor described him as `` a polite and friendly boy . ''

The tenor of the comments changed significantly once he was linked to Ritzer 's killing .

`` I 'd say he 's less ` polite and friendly ' than you thought , '' wrote one Facebook commenter . `` Everybody has to keep their eyes open . It 's no longer safe to say that you can take everybody at face value . ''

` The sweetest , most harmless person ever '

Ritzer graduated from Assumption College in 2011 , that school said on Twitter . She was pursuing a master 's degree in school counseling at Salem State University , that school said .

`` She believed children have much to offer and often do not realize how special they are as individuals , '' the university said . `` In her application to Salem State she said she was dedicated to ` helping students in times of need . ' ''

Charlotte Dzerkacz in 2011 taught at the same middle school with Ritzer , during which time the two became close friends .

At all times , Ritzer wore a wide smile and was approachable to students and colleagues alike .

`` She was energetic , she was compassionate , '' Dzerkacz said . `` You could n't ask for anything more from a teacher or a friend . ''

Like Dzerkacz , Ritzer 's aunt Shirley Martellucci said her niece never had any trouble with students -- including during the past two years , when she was at Danvers High .

`` She always wanted to be a teacher , all her life , '' Martellucci said . `` It 's just unbelievable that someone would take her life at such a young age . ''

On her Twitter account , Ritzer interspersed homework assignments and exhortations to work through tough math problems with cooking talk and inspirational messages .

`` No matter what happens in life , be good to people , '' she wrote in August . `` Being good to people is a wonderful legacy to leave behind . ''

Her family issued a statement seeking privacy as they mourn their `` amazing , beautiful daughter and sister . ''

`` Everyone that knew and loved Colleen knew of her passion for teaching and how she mentored each and every one of her students , '' the family said in the statement .

Students at Danvers High echoed that sentiment , as well as that of her school district describing Ritzer as `` a dynamic and brilliant ray of light . ''

In the halls , she was guaranteed to offer a warm smile . In class , she could be counted on to give an appreciated pat on the back . Even once the final bell sounded , she could always be counted on to offer teaching , guidance and support .

`` She was always the teacher -LRB- who would -RRB- go the extra mile for students , always the teacher to be there for students after school , '' said Kyle Cahill .

`` It 's just crazy . ''

Debate unfolds after teacher slayings in Nevada , Massachusetts

CNN 's Dana Garrett , Laurie Segall , Eden Pontz , Rob Frehse , Rose Arce , Chandler Friedman , Stephanie Gallman , Alexis Weiss and Bob Crowley , as well as journalist Alexandra Field , contributed to this report .

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NEW : The suspect went to a movie theater after allegedly killing his teacher , source says

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The district attorney says the suspect , Chism , was in one of Colleen Ritzer 's classes

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Her body is found in woods near Danvers High School in northeastern Massachusetts

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Complaint : Suspect 's interview with police , video evidence led to murder charge